The conservative movement is caught in a Catch-22 of its own making. In the war against "the establishment" we have made being an outsider the most important qualification for a politician. The problem? Once elected, outsiders by definition become insiders. This isn't just a semantic point. The Constitution requires politicians to work through the system if they're going to get anything done.

Look at all the senators who rode the tea party wave into power: Ted Cruz, Rand Paul, Marco Rubio, Ron Johnson, Pat Toomey, Mike Lee. To one extent or another, they are now seen as swamp things, not swamp drainers, by the pitchfork populists.

For example, Rubio was hailed as "The First Senator from the Tea Party" by the New York Times. But once he became a senator, he became ... a senator.

There's nothing wrong with that. It's his job. And obviously, policy choices matter. Rubio embraced immigration reform and it killed him with the talk-radio crowd. But there's a larger dynamic at work. It's like taking the job seriously is an automatic disqualification for the perpetually furious. Merely talking like a halfway responsible politician -- "we don't have the votes," "we have to pay for it" -- is proof of selling out.

Cruz's case is also instructive. Over the last decade, no politician more deftly hitched his political wagon to populist passions. He wore the animosity of his colleagues, including the GOP leadership, like a badge of honor. He was the leader of the insurrectionists. He had only one problem: He talked like a creature of the establishment -- largely because the Princeton- and Harvard-trained former Supreme Court clerk and career politician was one. He knew the lyrics to every populist fight song, but he couldn't carry the tune.

Until recently there was an "outsider" glass ceiling. The most strident populists -- Ron Paul, Herman Cain, Michele Bachmann -- could not get through the presidential primaries because the math wasn't on their side. At least half of the GOP doesn't want fire-breathers, so the winning candidate had to get a large slice of the traditional Republican vote and combine it with other constituencies. That's how Richard Nixon, Ronald Reagan, the Bushes, John McCain and Mitt Romney did it.

But Donald Trump not only jumped into the fray at the height of populist fervor, the field was also divided 17 ways. No one spoke less like a politician. No one who understood how governing works would have promised the things Trump promised -- health coverage for all, for less money, eliminate the debt, bring all those jobs back, etc. -- because they'd either know or care that such things are literally impossible.

President Trump has learned this simple fact the hard way. Yet for the first eight months of his presidency, his core supporters have stuck with him. The establishment remains the villain and Trump the hero for his willingness to say or tweet things that make all the right people angry. For his most ardent supporters, the fault for his legislative failures lies entirely with the swamp, the establishment or the "Deep State."

But Judge Roy Moore's victory last week in a runoff against Alabama Sen. Luther Strange may signal that the base is not Trump's army to command. Trump endorsed Strange, and -- contrary to the president's tweets otherwise -- that endorsement didn't help at all. The most important factor was Moore's demonization of the establishment, particularly Senate Majority Leader Mitch McConnell. The voters valued sticking their thumbs in the establishment's eye more than giving Trump a win.

What's both funny and sad is that there is remarkably little intellectual or ideological substance to the current populist fever. Strange was more conservative than Moore but less bombastic. Moore opposed Obamacare repeal and, until recently, couldn't say what DACA was. In other words, MAGA populism is less of an agenda and more of a mood. Meanwhile, the "Make American Great Again" crowd's initial preferred candidate in Alabama was Rep. Mo Brooks -- endorsed by radio hosts Sean Hannity, Laura Ingraham and others. He got crushed.

A lot of people are simply mad as hell and don't want to take it anymore. Republican politicians can't ignore the anger. Ideally, they'd channel it toward productive ends, as they did in the past. But further stoking the anger for political gain is not just ill-advised, it's pointless, because eventually, politicians have to govern.